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1.
The use of multifunctionalism to conceptualise contemporary rural landscapes has focused attention on the increased extent and impact of non-farmers in traditionally agriculture-based rural communities. Typologies of rural landholders have been developed as part of that research effort. However, those typologies are not grounded in established theory, including collective identity theory that could provide an important foundation for the study of occupational identity. Indeed, most quantitative studies may be flawed in drawing on only one of the seven elements contributing to collective identity. This paper examines the efficacy of relying on self-declared occupational identity through the analysis of rural landholder survey data in an Australian region. Tests for expected relationships between self-declared identity of farmer/non-farmer and social and farming variables expected to be correlated with occupation, such as property size, profitability, hours worked on- and off-property, enterprise type and membership of farming-related local organisations found that the expected relationships existed. It seems that self-declared occupational identity is a valid and cost-effective way to explore occupational identity amongst rural landholders. Collective identity, however, is complex and it is unlikely that important research questions can be adequately explored without a more holistic approach to the study of farmer identity in multifunctional landscapes. The paper concludes with a discussion of the potential benefits of moving beyond self-declared occupation to include other elements in the collective identity construct.  相似文献   

2.
Rural areas in developed economies are becoming increasingly multi-functional in that their character is being shaped by a mix of production, consumption and conservation values. Agriculture may remain the dominant land use, but many landholders do not see themselves as farmers by occupation. Researchers have demonstrated that occupational identity influences land use and management. However, efforts to explore the influence of occupational identity often rely on surrogate measures and have largely ignored identity theory. We build on research demonstrating that collective identity theory can be used to develop a valid and reliable measure of farmer identity and to then classify rural landholders across a natural resource management (NRM) region. The contribution of this paper is to explain how that measure of farmer identity can be mapped and then demonstrate the relevance of doing so for regional NRM in Australia. As expected, farmer identity varied across the case study region with distance from urban centres, and across different environmental assets. Those findings should lead to a more targeted approach to landholder engagement in NRM. We suggest that farmer identity (i.e. farmer-collective occupational identity construct; F-COIC) might provide a next step for responding to the challenges of interpreting and mapping multi-functionality.  相似文献   

3.
Connectivity initiatives typically require conservation action on private lands as a complement to public reserve systems, so they are more likely to succeed if underpinned by knowledge of the social factors influencing landholders' participation. Using a combination of social survey and market research techniques, we identify spatially referenced landholder segments. Using a number of behavioral and attitudinal constructs, including three psychographic constructs not previously used for identifying segments—sense of place, lifestyle motives, and nature values—we identify three lifestyler and two farmer segments, and show that the characteristics of lifestyler segments are more nuanced than previously thought. Preferences for four corridor connectivity initiatives are found to differ across landholder segments, which indicates the importance using a targeted approach for designing connectivity conservation programs. The results highlight the importance for achieving corridor connectivity of the Blue Collar Lifestyler segment, a lower sociodemographic segment not previously identified in the literature.  相似文献   

4.
Men and women interact with water resources and landscapes in different ways, and there are frequent criticisms that little research is undertaken across disciplines to address this issue. Biophysical scientists in particular struggle with how to integrate “gendered” water uses into models that are necessarily based on prevailing laws and equations that describe the movement of water through the hydrological cycle, independent of social constructs. We explore the challenges faced in developing interdisciplinary and transdisciplinary research approaches and then present a simple yet innovative socio-hydrological approach using participatory three-dimensional maps. As a case study, we describe undertaking this process in Ethiopia where two three-dimensional maps (men's and women's) were separately generated to represent the same 20 km2 landscape. Mapping results indicated important distinctions in how men and women view landscapes with regard to the number and types of ecosystem services identified. For example, only women identified holy water sites along streams, while men identified twice as many sacred trees on the landscape. There was a clear focus and detailed knowledge about soils among participants in both groups. Maps developed as part of this exercise were successfully used as the principal land use input for the Soil and Water Assessment Tool (SWAT) and results indicate that this is a valid strategy that enhances scientific knowledge and understanding of overall landscapes and ultimately adds value to research for development questions.  相似文献   

5.
Many streams in Westrn Australia are naturally saline. In others, especially in the south-western corner, land-clearance and other human activities in the catchment have accelerated rates of salinisation of surface and groundwater. Trends in surface water salinity are well-documented but the extent of penetration of saline stream water into the sediments has been little studied. As many of these streams have porous sandy beds and their flows may derive from groundwater, hydrologic exchange patterns between surface water and subsurface hyporheic water were hypothesised to govern the water chemistry of such rivers. We predicted high rates of hydraulic conductivity, leading to a close relationship between surface and subsurface (to a depth of 50 cm) salinity, and to a lesser extent, pH and dissolved oxygen. Where surface and hyporheic water differed in salinity, other chemical differences were hypothesised to be similarly marked, perhaps resulting from disjunct shallow subsurface aquifers. Triplicate wells were sampled from upwelling and downwelling zones of thirteen streams ranging in salinity from ca. 0.2 to 18 g L−1. Despite the seemingly-porous sandy beds at many sites, subsurface water chemistry only 20–40 cm below the bed sometimes differed markedly from surface water. For example, hyporheic water was only one-fifth the salinity of surface water at some saline sites (e.g., the Tone River) or 20 per cent more saline in streams with fresh surface water (e.g., the Weld River). At some sites of intermediate salinity (e.g., the Warren River), subsurface water was up to three times fresher than surface or downwelling water. Percentage saturation of dissolved oxygen in the hyporheic water was consistently low (<40%) whereas pH was more acidic than surface water, presumably due to microbial activity. Vertical hydraulic conductivity may be limited by layers of fine sediments and clays, implying that the meso-scale (1–100 cm) hydrological dynamics within the hyporheic zones of these rivers are more complex than their sandy beds would indicate. Assumptions of ecosystem dynamics in saline streams must be tempered by an understanding of hyporheic salinities as subsurface fresher water may support microbial and faunal assemblages excluded from the surface benthos by high salinity. In saline streams, as in fresh ones, the hyporheic zone is an important component of the stream ecosystem and equally prone to disruption by human activities.  相似文献   

6.
The Ramsar-listed Coorong lagoon lies at the terminus of the Murray-Darling River system in South Australia. Diatom and foraminifera relationships with water quality were characterised in order to develop diatom- and foraminifera-based models with the potential to infer water column salinity. Seventy-four samples were collected during 2007, a year of continuing drought in the catchment, and of no discharges at the Murray Mouth. The sample sites had a salinity gradient of 1.8–190 g l−1 total dissolved solids. The diatom data set comprised 215 taxa, while there were only eight taxa in the foraminiferal data set. Canonical correspondence analysis of diatom species-environment relationships showed that salinity explained the largest proportion of diatom variance. Hence, a diatom-based salinity transfer function with reasonable predictive power (measured vs. diatom-inferred salinity r jack2 = 0.82; Root Mean Squared Error of Prediction = 16 g l−1) was developed. Application of the transfer function to fossil diatom assemblages from The Coorong suggested that pre-European salinity values were generally >50 g l−1 and that salinity declined following settlement. These results, however, contradict the recent history of The Coorong where there have been substantial lagoon-wide salinity increases. The pre-impact diatom flora has no analogue in the modern data set, highlighting the degree of departure from past conditions. CCA of the foraminiferal data set identified salinity and total nitrogen as the variables with the greatest explanatory power. However, accurate predictive models could not be developed using either variable due to low foraminiferal abundance and species richness. These factors may have been a consequence of diminished foraminiferal recruitment rates over successive years, an artefact of reduced marine water input to The Coorong. Future attempts to generate predictive models from this region would benefit from the inclusion of data from distant locations, since suitable analogue sites do not exist in close proximity. The study has generated useful insights to the apparently broad salinity tolerances for several cosmopolitan diatom and foraminifera species, and has identified a number of diatom and foraminifera taxa that may prove useful in the qualitative interpretation of down-core trends in The Coorong and the lower Murray River region.  相似文献   

7.
The Kent River flows from semi-arid headwaters in the agricultural (wheatbelt) region of Western Australia to a wetter and forested lower-catchment. It is set in an atypical fluvial environment, with rainfall decreasing inland towards a low-relief upper catchment. Replacement of native deep-rooted perennial vegetation with shallow-rooted seasonal crops has altered the hydrology of the upper catchment. Clearing for agriculture has also increased recharge of regional groundwater systems causing groundwater to rise and mobilise salt stores. This has increased stream salinity which has degradation riparian vegetation and decreased flow resistance. Elevated groundwater has also affected streamflow, increasing flow duration and annual discharge. The altered hydrological regime has affected geomorphic stability, resulting in channel responses that include incision and removal of uncohesive material. Channel response is variable, showing a high dependence on channel morphotype, channel boundary material and severity of salinity (degree of vegetation degradation). Response in confined reaches bounded by sandy material has been characterised by minor lateral bank erosion. In the fine-grained, wider, low-gradient reaches, mid-channel islands have been stripped of sandy sediment where vegetation has degraded. Following an initial period of high erosion rates in these reaches, the channel is now slowly adjusting to a new set of boundary conditions. The variable response has significant implications for management of salt affected rivers in southwestern Australia.  相似文献   

8.
This paper explores the environmental knowledge of small-scale rural landholders and comments on the implications of this for environmental policy. The paper draws on conceptualisations of knowledge as 'know what', 'know why', 'know how' and 'know who', recognises a distinction between tacit and codified environmental knowledges and highlights the need to consider the politics of knowledge surrounding environmental issues. Both quantitative and qualitative data are reported, and are derived from structured interviews with 30 small-scale landholders who were participants in a nature and landscape conservation initiative – the Landscape Heritage Scheme – within South Devon, England. These data are used to explore the place of environmental concerns within the land management objectives of respondents; the nature and extent of their environmental knowledge; how a range of factors alongside their environmental knowledge shaped the environmental practices of respondents; and the politics of knowledge associated with the Landscape Heritage Scheme. The paper suggests that small-scale landholders should be of interest to environmental policy, prioritising environmental objectives in their land management, being relatively knowledgeable about the environment and highly responsive to environmental advice and financial incentives that support environmental management. A case is made for developing research in this area, given ongoing processes of rural demographic change and the rising importance within this of an increasingly diverse landholding population.  相似文献   

9.
Social capital has the potential to influence the success of biodiverse carbon plantings in the face of uncertainty amongst rural landholders about the need or efficacy of efforts to address climate change through tree planting. We conducted 17 face-to-face semi-structured interviews with landholders in Victoria, Australia who voluntarily participate in biodiverse carbon plantings on their land, focusing in particular on the role of social capital for understanding how ‘early adopters' can advocate for programs locally. The interviews revealed the importance of social networks and the profound impact of trusted peers on the diffusion of carbon planting schemes. These social capital dimensions are especially important for shaping ongoing participation and the ways in which participants become active agents in trusted relationships that influence the participation of others. Our results suggest that the positive impact of social networks can counteract doubts about the validity of climate adaptation responses such as carbon planting, and enable landholders to connect the program with their existing stewardship motivations. The ability for early adopters of the program to demonstrate the physical materialisation of their plantings to others was vital to this process. We propose that targeting champions and trusted peers in local communities could accelerate the proliferation of biodiverse carbon planting schemes.  相似文献   

10.
In this short communication, we report on dissolved organic and inorganic carbon concentrations from a summer stream monitoring campaign at the main hydrological catchment of the Tarfala Research Station in northern Sweden. Further, we place these unique high‐alpine observations in the context of a relevant subset of Sweden's national monitoring programme. Our analysis shows that while the monitoring programme (at least for total organic carbon) may have relatively good representativeness across a range of forest coverages, alpine/tundra environments are potentially underrepresented. As for dissolved inorganic carbon, there is currently no national monitoring in Sweden. Since the selection of stream water monitoring locations and monitored constituents at the national scale can be motivated by any number of goals (or limitations), monitoring at the Tarfala Research Station along with other research catchment sites across Fennoscandia becomes increasingly important and can offer potential complementary data necessary for improving process understanding. Research catchment sites (typically not included in national monitoring programmes) can help cover small‐scale landscape features and thus complement national monitoring thereby improving the ability to capture hot spots and hot moments of biogeochemical export. This provides a valuable baseline of current conditions in high‐alpine environments against which to gauge future changes in response to potential climatic and land cover shifts.  相似文献   

11.
Interactions between aeolian and fluvial systems in dryland environments   总被引:14,自引:0,他引:14  
Historically, fluvial and aeolian processes in dryland environments have been viewed as mutually exclusive. However, recent research indicates that in many regions dryland aeolian and fluvial systems do not operate independently. There are interactions between the two systems that have important implications for the geomorphology of the landscape. This paper reviews the factors controlling the transfer of sediments between aeolian and fluvial systems, focusing on moisture availability, sediment supply and the magnitude/frequency characteristics of fluvial and aeolian events. We conclude by highlighting areas of future research that will contribute greatly to our understanding of aeolian–fluvial relationships in dryland areas.  相似文献   

12.
The position of mountain streams high in the channel network and their proportional dominance mean that channel modifications and adjustments within these systems will have important implications for downstream processes and linkages. This study develops an analysis framework for examining the catchment-scale distribution of reach morphologies, and the relationship among reach type, catchment lithology and flow competence in southeast Australian mountain streams. The analysis framework is applied to three catchments which have contrasting proportions of the two dominant lithologies of the region, Devonian granites and Ordovician metasediments.The model successfully delineated 68% of reach types, and the resultant spatial maps allowed the effects of stream network position and catchment specific controls on channel morphology to be evaluated. Maximum lengths of the majority of reach morphology types were in second-order streams and the maximum number of morphology types (six) was present in third-order streams, with dramatic reductions in reach type variability as the network expands. The position of catchment lithology within the channel network structure was recognized as more important than the aerial extent of a particular lithology on the distribution and abundance of reach morphologies. The model provides an important tool in the management of channel networks for the protection or restoration of ecological diversity, by identifying river segments and tributaries with high morphological diversity.  相似文献   

13.
Active participation in the outdoors not only provides enjoyment and adventure, but it is also important for health and promoting conservation values. The latter is particularly important for young people as they are at an impressionable stage in their lives. Geographical accessibly of recreation opportunities can be a major barrier to utlization of the New Zealand outdoors. While it would be ideal to have a variety of opportunities available to everyone regardless of residence, the distribution of opportunities is constrained by the extent of suitable lands. This research provides a population based assessment of the geographical accessibility of recreational opportunities. Accessibility has many dimensions and includes cultural, financial, and geographical barriers; therefore this research is only addressing one dimension of accessibility. Geographical Information Systems is used for the analysis, which involves a function called least-cost path analysis. This identified the travel time (using a private vehicle) via the quickest route from where people live (represented by census enumeration points) to the entry point of the recreation sites. The outputs of this research are maps and spatial statistics on the travel times to a range of recreation opportunities for different parts of New Zealand. This information is important for recreation planning. In addition, the information also provides research opportunities for modelling recreation use, especially when accessibility information is combined with landscape experience information and recreation usage statistics.  相似文献   

14.
The traditional use of land for food, fuel and wood created cultural landscapes, which are threatened across Europe. The factors which contributed to their endangerment need to be identified to achieve effective preservation of such landscapes. The aim of our study was to identify landscapes with historical persistence in a GIS-based comparative analysis of historical and contemporary maps and the most prominent causes of the past landscape changes, based on stakeholders' perspective. We considered a case study in Romania's Carpathians. Three major land cover types were extracted from maps dating from 1912, 1980 and 2009: built-up, pastures and forests. The historical persistence of all land cover types was poor (<20%) and profound changes were quantitatively confirmed. Large, compact patches of unchanged forests were located in the neighbourhood of a national park. The persistent pastures were situated close to human settlements, and their preservation can be related to local traditional agro-silvo-pastoral management. Although the built-up area has increased over time, the corresponding surfaces are small and consist of scattered patches located around historical monuments. Semi-structured interviews were conducted to investigate stakeholders' perspective. Using cluster analysis five prominent causes of past landscape changes are identified: 'increasing tourism', 'land tenure and social changes', 'land-use intensification', 'post-communist transition', and 'foreign investments'. We join the results of the GIS analysis with those from stakeholders' perspective to gain more insights into the landscape changes. This research offers important information that could be used for the further planning of these valuable cultural landscapes in order to avoid potential conflicts and degradation.  相似文献   

15.
The groundwater recharge-discharge model, or hydro-equilibrium model, has driven Victorian dryland salinity research for the last 30 years. This paper challenges its application to the Dundas Tableland, south-western Victoria, on historical grounds. In exposing the weak historical foundation of the model for one geographical area so well represented in mainstream investigations, the critique is designed to question the validity of applying the model to other parts of Australia without corresponding historical research. More generally, it is hoped that this contribution from another discipline gives a respectful but significant nudge to the hegemony of physical science in defining and finding solutions for environmental problems.  相似文献   

16.
The natural eutrophication of lakes is still an accepted concept in limnology, arising as it does from the earliest efforts to classify lakes and place them in an evolutionary sequence. Recent studies of newly formed lakes at Glacier Bay, Alaska, only partially support this idea, and suggest more variable trends in lake trophic development which are under local (catchment-level) control. Here we use sediment cores from several lakes in Glacier Bay National Park to examine the relationship between successional changes in catchment vegetation and trends in water-column nitrogen (a limiting nutrient) and lake primary production. Terrestrial succession at Glacier Bay follows several different pathways, with older sites in the lower bay being colonized directly by spruce (Picea) and by-passing a prolonged alder (Alnus) stage that characterizes younger upper-bay sites. Sediment cores from three sites spanning this successional gradient demonstrate that the variability in nitrogen trends among lakes is a consequence of the establishment and duration of N-fixing alder in the lake catchment. In the lower-bay lakes, diatom-inferred nitrogen concentrations rise and then fall in concert with the transient appearance of alder in the catchment, while in the upper bay, high nitrogen concentrations are sustained by the continuous dominance of alder. Diatom accumulation, a proxy for whole-lake biological productivity, increases steadily at all three sites during the first century following lake formation, but declines in more recent times at the lower-bay sites in apparent response to the disappearance of alder and decreasing lake-water nitrogen. These results demonstrate a tight biogeochemical coupling between terrestrial succession and lake trophic change during the early developmental history of Glacier Bay lakes.  相似文献   

17.
黄河三角洲多尺度土壤盐分的空间分异   总被引:20,自引:5,他引:15  
王红  宫鹏  刘高焕 《地理研究》2006,25(4):649-658
本文利用多尺度采样数据,探索了两个深度土壤盐分的空间分异,分析了不同尺度、深度土壤盐分的变异系数和空间相关性(结构方差与基台值之比)的变化,揭示了形成这种空间变异的地貌因素,最后利用普通克立格(ordinary kriging)方法对土壤盐分的分布进行了估测。分析发现,研究区土壤盐分的空间变异具有三个尺度。随着采样间隔的增加和区域的扩大,盐分分布空间相关性增强,且下层比上层具有更高的空间相关性。地貌因素(微地貌类型、坡度和高程)均具有较高的空间相关性,当与地貌因素关系密切时,该尺度及深度的土壤盐分空间相关性就大;反之,则小,这时可能主要受具有较小空间相关性其他因子的影响(如人为活动)。最后对合理的土壤采样提出了建议。  相似文献   

18.
Rivers in drylands typically are characterized by extreme flow variability, with long periods of little or no flow interspersed with occasional large, sometimes extreme, floods. Complete adjustment of river form and process is sometimes inhibited, resulting in a common assumption that equilibrium conditions may rarely, if ever, exist in dryland rivers, and that transient and unstable (nonequilibrium) behavior is the norm. Examples from the Channel Country and the Northern Plains in central Australia challenge that notion. Along the middle reaches of these intermediate and large, low-gradient rivers, where long duration floods generate moderate to low unit stream powers and boundary resistance is high as a result of indurated alluvial terraces, cohesive muds or riparian vegetation, there is evidence that: (1) channels have remained essentially stable despite large floods; (2) sediment transport discontinuities, while present at a catchment scale, are largely insignificant for channel form and process in individual reaches; (3) there are strong correlations between many channel form and process variables; and (4) many rivers appear to be adjusted to maximum sediment transport efficiency under conditions of low gradient, abundant within-channel vegetation and declining downstream discharge. In these middle reaches, rivers are characterized by equilibrium conditions. However, in the aggradational lower reaches of rivers on the Northern Plains, where upstream terraces are buried by younger sediments and channels are less confined, nonequilibrium conditions prevail. Here, channels sometimes undergo sudden and substantial changes in form during large floods, sediment transport discontinuities are readily apparent, and landforms such as splays remain out-of-balance with normal flows. Hence, dryland rivers can exhibit both equilibrium and nonequilibrium conditions, depending on factors such as catchment size, channel gradient, flood duration, unit stream power, channel confinement, sediment cohesion, and bank strength. [Key words: dryland rivers, floods, equilibrium, nonequilibrium, central Australia.]  相似文献   

19.
Sometimes regional meteorological anomalies trigger different types of mass movements. In May 1998, the western Black Sea region of Turkey experienced such a meteorological anomaly. Numerous residential and agricultural areas and engineering lifelines were buried under the flood waters. Besides the reactivation of many previously delineated landslides, thousands of small-scale landslides (mostly the earthflow type) occurred all over the region. The earthflows were mainly developed in flysch-type units, which have already presented high landslide concentrations. In this study, three different catchments — namely Agustu, Egerci, and Kelemen — were selected because they have the most landslide-prone geological units of the region. The purposes of the present study are to put forward the spatial distributions of the shallow earthflows triggered, to describe the possible factors conditioning the earthflows, and to produce the shallow earthflow susceptibility maps of the three catchments. The unique condition units (UCU) were employed during the production of susceptibility maps and during statistical analyses. The unique condition units numbered 4052 for the Agustu catchment, 13,241 for the Egerci catchment and 12,314 for the Kelemen catchment. The earthflow intensity is the highest in the Agustu catchment (0.038 flow/UCU) and lowest in the Egerci catchment (0.0035 flow/UCU). Logistic regression analyses were also employed. However, during the analyses, some difficulties were encountered. To overcome the difficulties, a series of sensitivity analyses were performed based on some decision rules introduced in the present study. Considering the decision rules, the proper ratios of UCU free from earthflow (0) / UCU including the earthflow (1) for the Agustu, Egerci and Kelemen catchments were obtained as 3, 6, and 5, respectively. Also, a chart for the proper ratio selection was developed. The regression equations from the selected ratios were then applied to the entire catchment and the earthflow susceptibility maps were produced. The landslide susceptibility maps revealed that 15% of the Agustu catchment, 8% of the Egerci catchment, and 7% of the Kelemen catchment have very high earthflow susceptibility; and most of the earthflows triggered by the May 1998 meteorological event were found in the very high susceptibility zones.  相似文献   

20.
Elevated soil salinity is often associated with Tamarix invasion; however, it's unclear whether soils are more saline because of Tamarix or other environmental factors. Surface soil salinity was investigated along a flow-regulated, arid river with dense Tamarix of varying age to determine which factors best explain soil salinity. Flooding was the most important predictor, reducing salinity by nearly 70%. Soils under Tamarix had lower salinity than adjacent areas without woody cover in non-flooded areas suggesting that evaporation in arid environments may contribute more surface salts than Tamarix or may exacerbate plant inputs. Under most conditions, higher salinities were found under Tamarix than natives. An exception to this pattern was that soils under the smallest trees were more saline for natives. Relationships between soil salinity and stem size suggest that salts increase over time under Tamarix unless they are removed by flooding. However, the most mature stands had lower salinity than expected, reflecting some additional mechanism. Soil texture and distance from the river were important, but interacted strongly with other factors. The observed relationships between surface soil salinity and Tamarix stem size, a predictor of aboveground age, suggest Tamarix plays an active role in floodplain salinization within the sampled area.  相似文献   

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